Disney is sending a warning to moviegoers that Incredibles 2 may cause epileptic seizures.

CNN reports that while the House of Mouse is enjoying a record-breaking opening weekend with $180 million in the box office and the highest animated movie opening ever, not all fans are thrilled about the Disney-Pixar film.

Incredibles 2 includes several scenes with the villain ‘Screenslaver’ using a weapon that involves flashing lights. After the film debuted on June 15, fans went to Twitter to express their anger.

One fan Tweeted:

TO ANY FRIENDS WHO HAVE EPILEPSY, SEIZURE DISORDERS OR LIGHT SENSITIVITY: please be careful if you’re seeing the Incredibles 2.  I unfortunately had an issue and don’t want this happening to anybody else.

Here are more Tweets:

The Epilepsy Foundation has urged Disney on Saturday to issue a warning, and Disney complied, sending notices to movie theaters to post which fans thanked them for their swift action.